Bag filling tube and associated bag top gripping apparatus



June 1953 N. A. SCRANTON El Al 43,804

BAG FILLING TUBE AND ASSOCIATED BAG\TOP GRIPPING APPARATUS Filed Nov. 2. 1948 7 Sheets-Sheet 1 39 firs-T 95 PIA I) I I 5 I 1| I a "A, MA 5 gr INVENTOR. 39 fil/omgarzd'rrzaaicrarzrz mawzdrewmuia aflfi June 30, 1953 N. A. SCRANTON ET AL 2,643,804

BAG FILLING TUBE AND ASSOCIATED BAG TOP GRIPPING APPARATUS Filed Nov. 2; 1948 7 Sheets-Sheet 2 June 30, 1953 N. .A. SCRANTON ET AL 2,643,804

BAG FILLING mam AND ASSOCIATED BAG TOP GRIPPING APPARATUS Filed Nov. 2. 1948 7 Sheets-Sheet s Mrmarz Em 5cm Mai/2m Jizdrew Wlaie,

I I M. II I I I .i .II .16! I. II I I I II I I IW 7 I I iLk 6 Z W. M L I 6 I M w W n T w I,

0 w I I I I F T I. I r I June 30, 1953 N. A. SCRANTON ET AL BAG FILLING TUBE AND ASSOCIATED BAG TOP GRIPPING APPARATUS Filed NOV. 2. 1948 67 I'.' 5 g Z5 'r sneets-sne et 4 MV AW June 30, 1953 N. A. SCRANTON ET AL 2,643,804

BAG FILLING TUBE AND ASSOCIATED BAG TOP GRIPPING APPARATUS Filed Nov. 2. 1948 v 7 Sheets-Sheet 5 IN V EN TO 5- N'amzarz Jmflamn 1mm ma Maze,

June 30, 1953 N. A. SCRANTON El AL 2,643,304

BAG FILLING TUBE AND ASSOCIATED BAG TOP GRIPPING APPARATUS Filed Nov. 2. 1948 7 Sheets-Sheet 6 efifi INVENTOR JVO/UZQR 877205 501m; 22 Mama J/zdrew )V/uze, @M @VW/fi WW June 1953 N. A. SCRANTON ET AL 2,643,804

BAG FILLING TUBE AND ASSOCIATED BAG TOP GRIPPING APPARATUS Filed NOV. 2. 1948 7 Sheets-Sheet 7 Patented June 30, 1953 BAG FILLING TUBE AND ASSOCIATED BAG TOP GRIPPING APPARATUS Norman Amos Scranton and Mathias Andrew White, Decatur, Ill., assignors to ARE. Staley Manufacturing'Company, Decatur, 111., a. corporation of Delaware Application November 2, is4sjs'erial No.. 58,006

13 Claims.

1 '1 The; present invention relates to improvements inpacking apparatus of the typeadapted for use in connection with the filling of meal, granular,

powdered or other fluent materials into open mouthed bags of cotton, burlap, paper or similar flexible material.

' It. is a general object of the invention to provide a filling and packing apparatus comprising a packing tube and cooperating pairs of movable gripper members-which grip the margins of the bag when the mouth of the empty bag isplaced over the packing tube by the operator and auto matically hold the bag in proper position while it. is ,beingfilled and packed with the material andwhieh. thereafter deliver the filled bag to a conveyor without the, need'for any further handling. of the bag'by theoperator.

LIt isa more specificvobject of the invention to provide, a bag packingtube havingsupported thereon. a pair of relativelymovable gripper sup: porting ring members in combination with suitable automatic operating mechanism for manipulating the-grippers and moving the rings relative to each other to grip the margins of the open mouth of abag and move the bag in telescoped position over the endof thepacking tube, .to control the movementof the bag during. filling of the bag in such a manner as to cause the material to be uniformly packed from the bottom to .theltop f the bag while. the. bag is Withdrawn from. the packing tube and thereafter to releasethe filled and; packed bag onto a conveyor.

..It isa furtherobjectv of. the .inventionto promargins of the bag materialadjacent the mouth thereoiand move the bag in telescoping relation ontothe packingtube, to thereafter clampthe bagma-rgins externally and control therdescent of the .bag. while it is. filled uniformly from the.

bottomtothe top and finally to release the filled bag for deposit on a delivery conveyor.

It-isa still more specific object of the inventionto providea bag packing-apparatus of the class described having a packing tube andapair of'cooperating upper and lower ring-members movably mounted thereon, the lower ring member being providedrwith movable gripper elements for internally gripping the marginal portions of a bag and. the upper ring member being provided with movable gripper elements .for externally gripping the bag, the gripper elements on the lower ring member bein operable to grip the 2 bag while thelower ring member moves upwardly into engagement .with the upper ring member where the gripper 'elements thereon are auto; matically' disengaged and the gripper elements on theupper ring member are operatedto' engage theb'ag; the ring members being thereafter moved downwardly togetheriwhile the. bag is being filled and then separated after the gripper elements on the upper ring are operated torelease the bag for deposit/on a discharge conveyor beneath the packing ap-,

ing the bag top gripping mechanisms on the packing tube in the uppermost position;

Fig. 4' is a transverse section through the pack,- ing tube, takenv generally on the line 4-4 of Fig. 3;

Fig. 5 is a transverse. section through the packing tube, taken generally on the line 5--5.of Fig. 1;

Fig.6 is an elevation toanenlarged scale .of one of the internal bag gripping-elements;

Fig. 7 is.a..sectional .view, taken generallyon the line' 7-'7. of.Fig. 6;

Fig.8 is..an..elevation to an enlargedscale of one. of theexternal bag gripping elements;

Fig.9 is a sectional view, taken, generally on the-line indicated at llll0 of. Fig. '8, withthe gripper member and associated elementsshown partially in elevation andv withthe gripper member in.. closed position.

Fig. 10 isla sectional view, taken generally on the line indioatedat iii-4 0 of Fig. 8 but showing thegripping element in open position;

.Fig..1l is a vertical section, taken generally on the.line.llll of-Fig. 4; and

Figs. 12 -17 are schematic views illustrating the cycle. of operationswhich occur in positioning an empty bag on the packing tube and filling and removing the same.

The apparatus which is disclosed in the drawings incorporates therein the principles of applicantsinvention and is particularlyadaptecl to grip the open mouth of. a. bag, move the bag in telescopedrelation over a packing tube, deliver into "the bag in a uniformly packed manner a Figs. 12 to 17 which schematically illustrate the cycle of operations. The bag II] is positioned by the operator with the open mouth over the end of the packing tube II, and the machine is then actuated to automatically engage the bag, fill it with a charge of material, and deposit the filled bag on the discharge conveyor I2. 1

The lower gripping mechanism I3 is first started on its upward movement andits gripper elements are automatically operated to engage the inside of the bag top (Fig. 12). The upper. gripping mechanism It is retained in its uppermost position and the scale hopper I5 is filled with material ready to deliver a measured charge by operation of the gate I6. While the lower gripping mechanism I3 moves the bag I0 upwardly into telescoping relation over the filling spout II, the gate I6 is operated to deliver a charge of material H which falls by gravity into the packing tube II (Fig. 13) in position for delivery into the bag by the packing auger Ill. The mouthof the bag In is moved into position for engagement by the upper gripping mechanism I4 and the gripping elements on the lower gripping mechanism I3 are automatically moved out of engagement with the bag. The packing auger I8 (Fig. 14) delivers the charge of material into the bag while the bag I0 is moved downwardly with the upper and lower gripping mechanisms I4 and I3, respectively, moving .downwardly with the top of the bag. When the packing auger l8 has forced the entire charge of material I'I into the bag IIJ the gripping mechanisms I3 and I4 are at their lowermost position with the top of the bag still gripped by the upper gripping mechanism I4 (Fig, 15). The upper gripping mechanism I4 is then operated to release the filled bag I0 and started on its return movement to retracted or initial position at the top of the packing tube I I. The bag I0 with the charge II packed therein is allowed to drop onto the top run of the discharge conveyor I2 (Fig. 16). The lower gripping mechanism I3 remains in its lowermost position at the bottom of the packing tube II with the bag gripping elements in retracted position. As the filled bag It is moved by the conveyor I2 from beneath the packing apparatus the mouth of an empty bag is positioned over the lower gripping mechanism I3 (Fig. 17) and the machine is again operated to repeat the filling cycle. 7

Referring now to Figs. 1 to 12,the details of the apparatus are shown. The packing tube I| (Figs. 1 and 2) is cylindrical in form and arranged vertically with the upper portion I9 of the tube extending laterally and upwardly to form a chute beneath the scale hopper I5 which supplies the material for filling the bags. The hopper I5 is provided with a gate I6 which is operated in any conventional manner to permit a predetere mined amount or charge H of the filling material to fall into the chute forming section I9 of the packing tube'I I and down into the lower end portion thereof where it is delivered to the bag by the packingauger |8. The packing tube II and its upper chute forming section I9 may be supported on a conventional frame structure 20 such as the crossed channel members illustrated.

The frame structure 28 also supports the packing auger I8 and its operating mechanism. The auger I8 is mounted on a vertical shaft 2| which extends through a packing gland 22 in the upper wall of the offset upper section leof the packing tube I I. The auger shaft-2| is supported by spaced bearings 23. and is provided at its upper end with a miter gear 24 which engages with a miter gear 25 on the cross shaft 26. The cross shaft 26 is journaledin spaced bearings 2i, supported on the frame structure 20 and provided at one end with a pulley 28 which is connected by a belt 29 with the drive pulley on the motor 30. The driving motor 38 is supported on the frame structure 20. The auger shaft 2| is operated continuously by the motor 30 and packs each successive'charge of material into a bag it] while the bag is forced from the packing tube II by the packing pressure.

The packing tube II supports the cooperating lower and upper gripping mechanisms I3 and I4. The lower gripping mechanism I3 (Figs. 6 and 7) comprises a ring-like band member 32 which sur-v rounds the packing tube II and which is guided for vertical movement thereon by circumferentially spaced pairs of vertically spaced guide roll-"- ers 33 arranged adjacent the top and bottom.

edges of the band member 32. The guide rollers 33 (Fig. 11) travel in vertical groovesv 34 in the outer surface of the packing tube I I.

The band member 32 forms a carrying frame for the relatively flat, plate-like bottom gripper elements 35, which are pivotally mounted on cross pins 33 journaled in the lower end of the brackets 31. The brackets 31 are circumferentially spaced and extend outwardly and upwardly from adjacent the upper margin of the bandmember 32. Each bracket 31 comprises two spaced parallel plates 38 and two oppositely disposed brackets 31 are pivotally connected at 38 with the ends of vertically disposed strap members or chains 4|. The strap members 4| extend upwardly for connection with a counterweight operating mechanism which will be subsequently described. The band member 32 is suspended in this manner from the straps II and is moved vertically rela- 35 is received in its retracted position within a slotted recess 42' in the band member 32. The lower end of the gripper plate 35 is slotted at 43, forming two leg portions which are provided with outwardly projecting detents 44 or a knurled surface for better engaging the inner margins of the bag l0. At its pivoted end the gripper plate 35 is provided with an integral outwardly projecting arm portion 45 which is slotted at the ends and apertured to form bear.

ings for a cross pin 46, The pin 46 forms a lower cross head on an upwardly extending pull rod 41. The upper end of the pull rod 41 is provided with an enlarged head 48 having a tapered lower shoulder 49 which seats in an apertured socket 50 in a movable hollow plunger member 5|. The upper end of the plunger 5| is capped at 52 and adapted to be engaged by a'stop pin carried on the upper gripping mechanism I4 which will be subsequently described. The plunger member 5| is-provided With an intermediate exterior shoulder 53 which is engaged by one end of a compressionspring; 54. The other end of the compression spring 54 is seated'on a cross plate 55 extending between the side wall plates 38 of the bracket 3? at an intermediate-point. The cross plate 55 is aperturedat 56'to provide clearance for a compression spring 51 whichextends from theshoulder 5501a the plunger member to a washerliB' secured adjacent the pivot pin 46.

*When the movable plunger member 5| is depressed as in Figs. 6 and '7; the spring 5'? urges th'e gripper plate te'towards its withdrawn positicnwithin the 'rec ess 42 in the band member 32. When the plunger member M is freed it will move upwardly until the external shoulder 53 engages with the apertured guide and stop plate 59- on thebracket 37 and the pull rod M will pivot the gripper plate 'about the pivot pin 36 to thebag top engaging position provided the" gripper plate 35 is free to move. The spring 54' is-stronger than thespring M and when the plunger 5i is free to move upwardly it will move the full distance to bring the external shoulder Edinto engagement withthe stop member 59, unl'essthe gripper plate 35 is held against movementor'engagement with'the bag materialand complete outward movementof the same is prevented.

Wedgeshaped'members55%) are'provided on the bottom extremity of the packing chute H at the lower ends :of the. recesses d2 in position to be engaged-in latching relation in'the slots 43 in the lower ends of grippercplates 35 when the lower gripping mechanism I 3 is moved to its lowest position with the gripper plates 35 held in retracted position'so that the baglll may be placed thereover bythe'operator at the beginning of the'cycle of operations.

The upper gripping mechanism l4 comprises two concentrically arranged inner and outerband or ring members Bi and 62; surrounding the packing tube H Figures 8 to 11). The inner band member BI is provided'with circumferentially spaced pairs of rollers 63 which, are received in the guide recesses 34' in the outer surface of the packingtube H. The outer band member 62 which islarger in diameter than the inner band member fills telesccped over and slides on the outer surface of. the inner band member 6|. It is also narrower-or of less depththan the inner bandmember 5!. The inner band member 6! issprcvided adjacent its lower edgewith four pairs pfoutwardly extending pivot earsifid which provide supports for pivot pins 65. on which are mounted the external bag; gripper members'or elements The gripper members-'66 extend downwardly from the lower edge of' inner band member 6! and are swingable in an outward direction. Theyiare provided at'their ends with rubber pads -61 for gripping the external margins of the bag it against the surface of the band member 32 onthe lower gripping mechanism l3 whenthe latter is positioned in juxtaposederelation tothe upper. band member Bl (-Fig. 3). Each gripper member 56 is also provided with an abutment shoulder member 68 which is adapted to enga e belowv a cooperating abutment shoulder is on the lower band member. fizsothatthe band member. 22 may be locked against vertical movement-relative to theupper band member 5! when the, gripper members 65 areengagedwith the margins of the bag in clamping relation against the lower bandmemher-Q32 (Fig.9). Atoggle link member H3 is pivotally ,connectedat one endat H to the gripper memberfilia short distance below the pivot fill aces-p04 e pin 65 and at itsother end to a pin 12 journaled between dependingspaced bracket mem-'- bore 13- which extend upwardly and inwardly and are secured to theouter band member 62. Movement of the outer band member 62 relative to the inner band member 6| pivots the gripper member'tt toward and from the packing tube II by alignment above the bracket members 13 on the 'Each trunnion mem-' outeriband member 52. beri'i: supports a depending arm or link 18 having a. roller member '59 journaled in its bifurcated lower end. The upper end of arm 18is bifurcated and pivotally mounted on a pin 88.-

Thezarmlt is urged in a counterclockwise direction by a torsion spring BI and functions as a latch for holding the outer band member (52 in its lowermost position relative to the inner band member El. by engagement with a stop plate 82 secured on the outer'band member 62 between the spaced bracketmember i3. Theroller 19 is adapted to engage the top ofthe stop plate 82 and hold the band member 62 andits assembly in the lowermost position.

In order to-releasethe gripper members 66 after the bag is filled and'when both lower-and upper gripping mechanisms ISiand l4 are adjacent the bottomof the filling spout II, a latch releasing pin 83*- is provided in a socketB-d which extends fromsthe -outer band member 62 through packing tube H during theupward movement of the upper gripping .mechanismwhile the gripper members 66 are not in gripping relation with the bag "top. :The recess '88 terminates in a cam forming end surface 823 ata spaced distance from the bottom end of the packing tube I l The card surfaceuliii is located to cause the pin 83 to be pressed outwardly at the bottom limit of the movementof the gripping mechanisms to engage the-rollerle and move it from its locking position above'the plate 32 to a position where it will ride on the outer surface of the plate 82 and permit theouterl band member 552 to move upwardly relativextothe inner bandv member 6i. The outer band member: 62 is limited in its upward movement relative to the inner'band member 6| by circumferentiall'y spaced. adjustable stop pins 9B which-are carried by the bracket members 71.

The outer bandmember 52 also carries adjustable s-top pins'ii l (Figs. 2, 6 and 7) on radially outwardly extending brackets 92 which are adapted to-engage 'the'upper ends'52 of the plunger memon the lower gripping mechanism as previously. described for retracting the internal gripper @181385'35111130 the recesses 42 when the lower band member reaches its uppermost position with the bag top marginsengaged by the gripper platesi35.

The packing tube II is provided with circumferentially spaced abutment forming members 93 (Fig. 10) which limit the upward movement of the upper gripping mechanism I4 by engagement with the outer edges of the outer band member 62.

. Rubber bumper members 94 are preferably arranged between the lower band member 32 and the upper band member 6I to cushion the shock of engagement when these members are moved into engagement with each other (Fig. 11)

In the illustrated apparatus the gripping mechanisms I3 and I4 are controlled in their movements by a counterweight 95 (Figs. 1 and 2) which is arranged above the packing tube and which operates with a vertical movement. The counterweight 95 is guided in its movement by a pair of spaced angle members 96, opposing flanges of which engage in slots 91 in the opposite sides of thecounterweight 95. At the lower end of the counterweight 95 there is provided a pair-of rotatable pulleys 98 which are arranged on opposite sides. A pair of pulleys 99 of similar size is'mounted on the frame structure'20 above the packing tube II at opposite sides adjacent the guide members 96. A pair of larger supporting pulleys I are rotatably mounted in spaced relation adjacent the upper ends of the guide members 96. The straps 4| which are connected at the ends 40 to the lower gripping mechanism I3 extend upwardly and over the pulleys I00, then downwardly and around the pulleys 98, then upwardly and around the pulleys 99 and downwardly to connect at their ends I6 to the upper gripping mechanism I4. By means of this arrangement both the upper and lower gripping mechanisms I3 and I4 are operated by movement of the single counterweight 95.

One of the large supporting pulleys I90 is provided with an inwardly extending pin l0I adapted to be engaged by one arm I02 of a latch member pivoted. at I63 to the frame 20 and having a depending arm I04 which is controlled by any convenient actuating means such as an hydraulically operated piston or the like. The counterweight 95 is connected at its lower end to the lower end of a plunger I05 which operates in an air cylinder I06 to provide smooth movement of the counterweight in a well known manner.

The operation of the gripping mechanisms 13 and I4 by means of the counterweight 95 is as follows: Assuming that the lower gripping mechanism I3 is in the lower position and the upper gripping mechanism I4 is in the upper position, the counterweight 95 will be in an intermediate position halfway between its lowermost and uppermost positions with the latch arm I02 engaging the pin IOI on the pulley I00. The mouth of the empty bag I0 is placed over the gripper plates 35 by the operator and the arm I04 is tripped by the starting mechanism to release the latch arm I02 from the pin IOI and permit the counterweight 95 to move downward toits lowermost position. As the counterweight 95 begins its downward movement the lower gripping mechanism I3 begins to move upwardly and the gripper plates 35 are released from engagement with the wedge members 60 and pivot outwardly into gripping engagement with the internal margins of the bag I0. Continued movement of the counterweight- 95 carries the lower gripping mechanisms I3 upwardly by movement of the straps 4I until the upper edge of the lower band member 32 engages the inner band member GI and moves the band member BI up relative to the outer band member 62, the outer band memher being held against upward movement by thebers 66 are held in clamping position by the rollers 19 on the latch arms I8 while the pressure of the material, as it is fed into the bag I0 by the auger I6, moves the bag downwardly and carries with it both lower and upper gripping mechanisms I3 and I4, causing the counterweight to move upwardly to its uppermost position. When the bag is completely filled and the gripping mechanisms I3 and I4 reach their lowermost position, the pins 83 are moved outwardly by the cam surfaces 89 in the slots 88 and the rollers 79 are moved out of latching engagement with, the top of plates 82, permitting the band member 62 to move upwardly relative to the band members 6| and swinging the external gripper members 66 outwardly about the pivots 65 to release the filled bag and also to disengage the abutmcnts 68 and 69 and free the upper gripping mechanism I4 for movement in the upward'direction. The counterweight automatically begins to drop when the external gripper members 66 release the filled bag I9 and the upper gripping mechanism I4 moves upwardly until it reaches its uppermost position when the latch arm i 02 automatically operates to engage the pin IQI and stop the counterweight in the intermediate position where it is ready for the next cycle of movement. The gripper plates 35 on the lower gripping mechanism I3 are held in the recesses 42 by action of the springs 54 and 51 during the downward movement of the gripping mechanisms' while the bag In is being filled, and when the lower limit of movement is reached the gripper plates 35 are held against outward movement by engagement with the wedge members 60 until the next cycle of operations starts the lower gripping mechanism on its upward movement.

Itwill be understood that the use of other mechanisms for operating the gripping devices is contemplated. While the counterweight arrangement in the illustrated apparatus provides satisfactory operation, it may be desirable to operate the gripping mechanisms hydraulically or electrically. Any suitable control may be employed to actuate the filling material delivery gate I6. Also the control for starting the movement of the counterweight 95 may be varied considerably and the particular mechanism shown for this purpose is merely illustrative.

While specificdetails of construction have been shown in the illustrated apparatus, it will be understood that other details of construction of an equivalent natureare contemplated within the spirit of the invention.

We claim:

1. In a bag filling apparatus wherein an empty bag is positioned on a filling spout and then withdrawn therefrom as the filling material is forced into the bag, mechanism for gripping the bag margins adjacent the mouth thereof and control ling the movement of the bag, said mechanism comprising a pair of spout encircling frame members, said frame members comprising upper and lower members which are initiallyseparated, means mounting-said frame members for axial movement on said spout, movable bag grippers mounted :on. saidframe members, and means for -moving:said bag grippers and said frame mem- .members relative to each other,v and control means for said counterweight, whereby'to position the mouth of an empty bag over the spout,

thereafter to retard the movement of the bag as it isforced from the spout by the filling operation and finally to automatically release the filled bag. 2; A bag packing apparatus comprising a packing' tube, a" pair of'u'pper and lower ringimem bers, means supporting said ring members on said tube for axial movement relativeto said tube and to each other, movable gripper elements "on said --low"er ring member for internally gripping" the marginal portions of a'ba'g, movable gripper elements on said upper ringme'mber for'extern'ally gripping the marginal portions of the bagymea'ns for operating the: gripperelements on said lower ring member to grip the bag when it is positioned thereon, means-formoving said lower ring member upwarolly. toward-said upper ring member to telescope the bagoverthe tube;means-for operating the gripperelements on 'saidupper ring' member to grip the b'a'g when said'lower ring member moves into engagement with said upper ring member, means for automatically disengaging the gripper elements on said lower ring member when said lower r-ing member-moves into engagement with said'upper ring' member, meansin said tube for forcing a charge of filling material into the bag and thereby forcing the bag *downwardl'y on said tube, means for retarding the-movement of-saidring members as they'are simultaneously forced downwardly by downward movement of the bag during the filling. operation, means for operating the gripper elements on saidupper ring member to release the bag when the filling operation is completed, and'means for returning said upper ring member to its uppermost position on said'tube;

3. A bag packing apparatus as'recited in claim 2 and interengaging means for locking said upp r andlciwer ring members together when said lower ring member moves into engagement with said upper ring member, said locking meansbei'n'g disengaged when'the filling operation is completed.

4. Packing'app'aratus comprising in combination, a vertical filling spout'to receive'theopen mouth of a flexible ba and means for freely suspending the bag by its mouth while it is being filled with material, said means compirsing a pair of relatively movable upper and lower circular frame members positioned around said spout, gripper members on the lower one of said frame members adapted for engaging the internal margins of the bag, gripper members pivotally mounted on the upper one of said frame members adapted for engaging the external margins of the bag to clamp the same against the lower frame member, an outer ring mounted for limited axial movement on said upper frame member, an operating link connecting each of said pivotally mounted gripper members with said outer ring member, means on said spout engageable with said outer ring member to limit the upward move- 11i) ment of the same; and means to move said lower frame member upwardly; into engagement with said upper frame member and thereby move said pivotally mounted gripper members into bag clamping engagement with the lower frame membeltv c ,7 5 Packing apparatus comprising a 1 vertical fillingrspout for receiving in telescoping relation thereover a flexible bag to be filled with material, upper and lower frame members mounted on said spout -for predetermined vertical-movement, cooperating. guide means on said spout a nd s aid-"frame members, said lower frame membersbeing initially positioned adjacent the-bottom end of said spout, said upper frame member being-initially positioned adjacent the upper end of-said-spout; bag gripper armsmounted on said frame members, the gripper arms on the upper frameinem-ber being'pivoted adjacent the'lower edge of said frame member, an outer ring member mounted'on said upper frame member for limited vertical movement relative thereto, means mounted on said spout for limitingthe upward movement of said outer ring member while permitting-further upward movement of said upper frame member, links pivotally connecting the gripperarms on the upper frame member with said outer ring member, and operating means to movesaid lower frame member vertically into engagement with said upper frame member and thereafter to move said upper frame member relative to said outer ring member tocau-se said links topivot the gripper arms on said upper frame member into clamping engagement with said lower frame member. I

6,- Packing apparatus as recited inclaim 5 and means for automatically latching said outer ring member to saidupper frame membcrupon predetermined upwardmovement of the latter.

7. Packing apparatus as recited in claim 6' and means for automatically-releasing said latch means upon predetermined downward movement of saidupper frame'member on-saidspout.

8. In a bag filling apparatus wherein an empty bagis positionedon a filling spout and then withdrawn therefrom as the'fill-ing material is forcedinto the bag-,amechanism for grippingthe bag margins adjacentthemouththereof and controlling'the movementof the bag, said mechanism comprising a pairof-spout encircling frame members, means mountingsaid frame members for relative-movement axially ofsaid spout, said mounting means :for saidframe members com prising circumferentially spaced, radially inwardly projecting guide rollers andsaid filling spout-being. provided with cooperating axially -extending,.grooves for receiving said guide mollers, movable ba grippers mounted on said frame members, and means for moving said bag grippers and said frame members in timed relation whereby to position the mouth of an empty bag over the spout, thereafter to retard the movement of the bag as it is forced from the spout by the filling operation and finally to automatically release the filled bag.

9. In a bag filling apparatus wherein an empty bag is positioned on a filling spout and then withdrawn therefrom as the filling material is forced intothe bag, mechanism for gripping the bag margins adjacent the mouth thereof and controlling the movement of the bag, said mechanism comprisin a members, means mounting said frame members for relative movementaxially of said spout, movable bag grippers mounted on said frame mempair of spout encircling frame and lower band members which are initially separated and wherein said movable bag grippers comprise bag engaging arm members pivotally mounted on the lower band member for automatic outward swinging movement to engage the inner margins of the empty bag upon upward movement of said lower band member, and means mounted on said upper band member to automatically pivot said bag gripper members on said lower band member out of engagement with the bag. when said lower band member moves upwardly into engagement with said upper band.

10. In a bag filling apparatus wherein an empty bag is positioned on a filling spout and then withdrawn therefrom as the filling material is forced into the bag, mechanism for gripping the bag margins adjacent the mouth thereof and controlling the movement of the bag, said mechanism comprising a pair of spout encircling frame members, means mounting said frame members for relative movement axially of said spout, movable bag grippers mounted on said frame members, and means for moving said bag grippers and said frame members in timed relation whereby to position the mouth of an empty bag over the spout, thereafter to retard the movement of the bag as it is forced from the spout by the filling operation and finally to automatically release the filled bag, said frame members comprising upper and lower band members which are initially separated and wherein said movable bag grippers comprise bag engaging arm members pivotally mounted on said upper band member for automatic inward swinging movement to engage the outer margins of the empty bag upon upward movement of said lower band member to a position in engagement with said upper band member, and wherein interengag- 'ing means are provided on said bag engaging arm members and said lower band member to lock said upper and lower band members together for simultaneous downward movement with the bag as the bag is forced from the spout by the filling operation.

11. In a bag filling apparatus as recited in claim 1 wherein said movable bag grippers comprise bag engaging arm members, means for 'pivotally mounting saidarm members on the lower band member, and means for automatically swinging said arm members outwardly to engage the same with the inner margins of the empty bag upon upward movement of said lower band member.

12. In a bag filling apparatus as recited in claim 1 wherein said movable bag grippers comprise bag engaging arm members, means for pivotally mounting said arm members on said upper band member, and means for automatically swinging saidarm members outwardly to engage the same with the outer margins of the empty bag upon upward movement of said lower band member to a position in engagement with said upper band member.

13. In a bag packing apparatus comprising a packing tube and upper and lower band members mounted in encircling relation to. said tube for movement relative thereto, bag engaging gripper devices on said lower band member each comprising a bag engaging plate member, a pair of spaced bracket members extending outwardly of said lower band member, pivot means mounting the upper end of said plate member at the lower end of said bracket members, an arm on the upper end of said plate member extending outwardly of said pivot means, an upwardly extending pull rod pivotally connected to the outer end of .said arm, a member slidably mounted in said bracket members for limited vertical movement, said member being movably connected to the upper end of said pull rod, compression spring means between said arm on said plate member and said slidably mounted member, compression spring means between said slidably mounted member and said bracket members urging said slidably mounted member and said pull rod in an upward direction to pivot said bag engaging plate member outwardly of said lower band member, and an abutment on said upper band member for engagement with said slidably mounted member when said upper and lower band members are moved into juxtaposed relation whereby to cause said compression spring between said arm and said slidably mounted member to swing said bag engaging plate member toward said lower band member.

NORMAN AMOS SCRANTON. MATI-HAS ANDREW WHITE.

References Cited in the file of this patent UNITED STATES PATENTS 

